1. Field of the Invention
The invention relates to a wire holding construction for a joint connector as well as to a joint connector provided therewith.
2. Description of the Related Art
Japanese Unexamined Utility Model Publication No. 5-65073 and FIGS. 10(A) and 10(B) herein disclose a joint connector 1 with housings 2a, 2b, 2c. Each housing 2a, 2b, 2c has cavities 3 with open upper surfaces for receiving insulation-displacement terminal fittings T. The terminal fittings T are inserted in the respective cavities 3 and connected to wires W. The housings 2a, 2b, 2c then are joined one over another to position and hold the terminal fittings T between the housings 2a, 2b, 2c. 
The insulation displacement terminal fittings T have slots that connect to the wires W without stripping the insulation coating of the wires W. However, pulling forces can withdraw the wires W from the insulation-displacement terminal fittings T, and the prior art joint connector 1 has no structure to prevent such withdrawal.
The invention was developed in view of the above problem and an object is to prevent wires from being pulled out of the joint connector.
The invention relates to a wire holding construction for a joint connector with a plurality of housings placed one over another. The housings have cavities for accommodating terminal fittings. The respective housings have wire draw-out portions, and wires connected with the terminal fittings are drawn out from the wire draw-out portions. Wire holders project in a wire draw-out direction from wire draw-out portions of the housings. Holding projections are formed on the inner surfaces of the wire holders and project substantially toward opposed inner surfaces. Thus, the wires are squeezed between the holding projections on the inner surfaces of opposed wire holders so that the wires will not come out.
The terminal fittings may be insulation displacement terminal fittings, and may have a small holding force against a wire pulling force. Small crimping terminal fittings that have a similarly small holding force also may be used.
The housings and the wire holders that are placed one over another may be joined by locks. The locks may comprise resilient claws that engage in grooves. The locks also may comprise projections that engage locking holes.
The wires drawn out from the respective housings can be held by the opposed holding projections of the wire holders while the housings are placed one over another and joined. The wire holders project from the housings substantially in the wire draw-out direction. Thus, the assembled joint connector can be handled while preventing the wires from being pulled directly during the operation.
Each holding projection may comprise ribs that extend at an angle to the wire draw-out direction. Thus, the wire is squeezed at spaced apart positions to provide enhanced resistance against pulling forces on the wire.
The wire holding portions may be formed separately from the corresponding housing and may be detachably attached to the housing. Thus, a change in the diameter of the wires to be held by the wire holders can be dealt with easily merely by preparing a plurality of kinds of wire holders and changing the wire holders. The housings may be used without attaching the wire holders if the joint connector is used where no pulling force will act on the wires.
Each wire may comprise a sheath for covering a plurality of thin parallel wires and may be squeezed between opposed holding projections so as not to come out. Thus, the wires can be held together by one wire holder, and a change in the diameter of the wires can be dealt with. Further, squeezing forces exerted by the holding projections are applied to the sheath and not directly to the wires. Thus, troubles such as fracture or breakage of the wires caused by squeezing can be avoided.
Guiding means are placed substantially one over another for positioning the wire holders with respect to each other.
The invention, also relates to a joint connector comprising a wire holding construction.
Locks may be provided for locking the housings together.
Preferably, one of the housings is formed as a lid for substantially covering an end portion of the joint connector.
Parts of the housings may be connected to each other by hinge means.
Most preferably, at least some of the housings are lockable to each other by hook means.
These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are described separately, single features thereof may be combined to additional embodiments.